Role of Fe2+ in Oxygen Sensing in the Carotid Body
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Prolyl hydroxylase is an enzyme which oxidatively modifies the proline residue of hypoxia inducible factor (HIF-lα) in the presence of oxygen in an apparently irreversible reaction. This reaction also requires labile Fe2+, 2-oxogluterate (2-OG) and ascorbic acid. Hypoxia retards this reaction and HIF-1α is accumulated. Similarly, Fe2+ chelation mimics hypoxia-like effect. Thus, the enzyme stands at the gateway between hypoxia and normoxia. The hy-droxylated HIF-1α undergoes proteasomal degradation during normoxia whereas HIF-1α, accumulated during hypoxia, binds with β-subunits to form HIF-1 which is then transcripted to various genes in the nucleus.
KeywordsIron Chelation Carotid Body Prolyl Hydroxylase Glomus Cell Mitochondrial Inhibitor
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